This invention relates to a method in accordance with the corresponding independent claim. The invention also relates to a device for implementing said method.

If a vehicle (automobile, heavy vehicle, motorcycle, watercraft, train or other mobile vehicle) is involved in an accident, it is known to be necessary to determine the causes thereof. In this respect, it often happens that if several vehicles are involved in the accident, considerable difficulties arise in defining responsibilities for the accident. This has considerable repercussions for insurance companies in determining and paying for damage suffered by the vehicles involved.

An object of the present invention is therefore to provide a method, and a device for its implementation, which enable the causes of an accident involving a moving vehicle to be determined such as to resolve any controversies relating to the accident.

A further Object is to provide a method of the stated type which is simple to implement.

A further object is to provide a device for implementing the aforesaid method which is reliable, which can be mounted on any vehicle (automobile, motorcycle, heavy vehicle, watercraft, train or other vehicle), which is able to operate for a very long time

without requiring maintenance and which can also operate in the presence of substantial environmental changes external to the device (considerable ambient temperature changes, thermal shock, immersion in water or corrosive, detergent or flammable liquids, or in the presence of fire).

These and further objects which will be apparent to the expert of the art are attained by a method in accordance with the corresponding main claim. Said objects are also attained by a device for implementing the aforesaid method in accordance with the corresponding independent claim and the other claims connected therewith.

The present invention will be more apparent from the accompanying drawing, which is provided by way of non-limiting example and _ϊn which:

Figure 1 is a front perspective view of the device according to the invention;

Figure 2 is a view similar to Figure 1 but with a part shown in section;

Figure 3 is a partly sectional, exploded partial view of the device of Figure 1 seen from above;

Figure 4 is a perspective view of the device of Figure 1 seen from the rear;

Figure 5 is a partly sectional, exploded partial view of the device of Figure 1 seen from the rear;

Figure 6 is a block diagram of part of the device of Figure 1 ;

Figure 7 is a block diagram of a modification of the part of

Figure 1 ;

Figure 8 is a block diagram of a further modification of the part of Figure 1 ;

Figure 9 shows a schematic example of the connection of the device of Figure 1 to the electrical power supply of the vehicle to which the device is connected;

Figures 10 and 11 show two further examples of the electrical power connection for the device of the invention.

Figure 12 shows a flow chart of the method according to the invention.

With reference to said figures and in particular to Figures 1 to 5 and 9 to 11, the device of the invention (indicated by D) comprises a box element 1 the interior of which contains an electronic circuit 3 (described hereinafter) for recording (and hence memorizing) images, obtained by a telecamera 4, of the environment in which a vehicle on which said device is mounted is in a moving or stationary state. The box element is hermetically sealed and is able to protect the circuit 3 from any external temperature variation and from attack by corrosive chemicals or flammable liquids, and by fire.

More specifically, the box element comprises removable box parts 10 and 11 on its front face 7 and rear face 8 respectively. The part 10 supports the telecamera 4 and contains the usual control members for the telecamera 4 (which for simplicity are to be considered as included within this latter term). This latter is advantageously a microtelecamera of known type, and preferably of the type for obtaining said images in digitized form. The telecamera 4 (including its control members) is connected to a series of connectors 13 projecting from the part 10 and arranged to cooperate with seats 14 provided in a face 15 of a central block 16 of the box element or casing 1. The seats 14 are blind and internally comprise usual contact elements 17 to which the circuit 3 is connected (in known manner and therefore not shown).

Likewise, the part 11 comprises a plurality of connectors 18 arranged to cooperate with seats 19 in the block 16 which are totally identical to said seats 14 and are arranged to allow a plurality of display and device control members provided on a face 20 of the part 11 to be connected to the circuit 3. These members comprise a light-emitting display 21 (for example an LED), a icrospeaker 22 (to indicate malfunction of the device D) and pushbuttons 23 and 24 to act on the circuit 3 a ^' nd modify its state of operability. Finally, the block 16 laterally comprises two connection members 25 and 26 to enable the device to be connected to a usual battery of the vehicle on which it is mounted, and to external members such as an external reading member for the data

memorized by the device. This latter can also be made to operate by a coded command generated by a remote control 27 (of radio- frequency, infrared ray or similar type) and/or by the vehicle ignition block 28 (Figure 9).

With reference to this latter figure, the vehicle ignition key 29 is known to be able to assume two different positions, namely a vehicle rest position (S) or a vehicle operation-enabling position (M) . When in this latter position, in known manner, it closes a mechanical contact 30 in a first electrical power branch 31 connecting the device of the invention to a usual vehicle battery 32. Parallel to the electrical branch 31 but connected to the same pole of the battery 32 as this latter branch there is another power branch 33 in which there is a mechanical contactor 34, which is open when the key 29 is in the position M. This power branch (or second branch) 33 is connected to the device of the invention independently of the contactor 30 and is also connected to a timer relay 35 arranged to operate on a mechanical contactor 36 connected into a first electrical return branch 37 connecting the device to the battery 33. The contactor 36 is normally open (as shown in Figure 7) when the key 29 is in the position M. Parallel to the branch 37 there is a second electrical return branch 39 in which there is a mechanical contactor 41 controlled by a relay 40 connected to the power branch 31 downstream of the contactor 30. The contactor 41 is normally closed when the key 29 is in the position M.

In this manner and following a vehicle start enabling signal originating from the block 28 (key 29 in position M) , the contactors 30 and 41 close to power the device. At the same time, following ^' vehicle stoppage (for example after an accident in which it is involved), the contactor 34 is closed and, for a defined time period set by the relay 35, the contactor 36 is also closed. In contrast the contactors 30 and 41 are opened. Consequently during the moments following vehicle stoppage the device D is operative and its circuit 3 is able to memorize (until the relay 35 opens the contactor 36 to interrupt connection to the battery

32) the images obtained by the telecamera 4. This enables both the causes of the accident and what occurs during the moments immediately after it to be verified in the most suitable manner. In this manner any controversy arising after the accident can be objectively resolved, and its causes and responsibilities be understood.

Figures 10 and 11 show two further circuit diagrams representing two different forms of powering, the first (Figure 10) usable for a device D comprising non-volatile image memory means (as described hereinafter) and the second (Figure 11) usable for a device D comprising volatile memory means. In these figures parts corresponding to those of the preceding figures are indicated by the same reference numerals.

In these figures, the voltage VB from the battery (not shown) powers a linear voltage adaptor 100 which changes the voltage and current to make them acceptable to the device D connected to the adaptor 100 via electrical branches 101 and 102. Between the branches 101 and 102 there is a branch 100A in which there is a buffer battery 103 (in series with an electrical resistor 104) to maintain the device D powered (by creating a stabilized voltage) even after a collision which damages the vehicle electrical installation.

From the branch 102 there extends a branch 105 comprising a mechanical contactor 106 controlled by the ignition key 29. When the key is in position M, this contactor closes onto a branch 107 connected to the branch 101 and in which there is a bistable relay 108 and a mechanical contactor 109. When the keyis in position S the contactor 106 closes onto a branch 110 connected to the branch 101 (and to which there is connecter ^' .• ^• • branch 112 comprising a timed relay or timer 113) connected to the relay 108, and in which there are mechanical contactors 115 and 116. This latter is controlled by the relay 113. In Figure 10 a further contactor 117 is positioned in the branch 101 upstream of the device D, whereas in Figure 11 (in which the contactor 117 is not present) a

contactor 118 is positioned in a branch 119 connected to the device D.

The contactors 109, 115, 117 and 118 are controlled by the bistable .relay 108.

During use, on turning the key to position M the contactor 106 is set to the position of Figures 10 and 11. The relay 108 is powered (via the normally closed contactor 109), so closing the contactors 115, 117 and 118 and opening the contactor 108. In this manner the relay 113 is set for operation and the device D is powered (together with all parts connected to it such as the telecamera). On turning the key to position S the contactor in the branch-is closed to power the relay 113 which with an inherent delay e ^' loses the contactor 116, to power the relay 108 via the branch 7f6A in which this contactor is located. This delayed powering of the relay 108 (or rather of its part -R, different from the part +R connected to the branch 107) causes this latter to operate on the contactor 109 (which closes) and on the contactors 115, 117 and 118 so as to disconnect the device from the power supply. As stated, this disconnection occurs with a delay enabling the device D to operate even after the vehicle has stopped (for example following a collision) . If the connection with the vehicle battery is interrupted following the collision, the buffer battery 103 enables the device to be powered for a predefined time following the collision.

The telecamera 4 is located on the vehicle in a position such as to allow optimum filming of the environment in which it is situated.- This telecamera can be incorporated into the box casing 1 (as shown) or can be distant therefrom and connected to it by usual electric cables. Alternatively more than one telecamera can be located on the vehicle in different positions, so as to film the environment containing the vehicle from a number of angles. In all cases the position of the telecamera on the vehicle (for example in its passenger compartment) depends on its shape.

As stated, each telecamera 4 is connected to a circuit 3 for recording the images obtained by it. Examples of this circuit are shown in Figures 6 to 8.

Such a circuit 3 comprises a control unit 50 connected to a communication bus 51 to which there are also connected: an analog/digital converter 52 connected to the telecamera 4 if this is not of digital image type; a known member for compressing data or rather the images obtained by the telecamera 4; a memory member 54 of the circular memory type, ie of the type using the FIFO (first in, first out) memorizing method, such as a flash memory member or RAM with buffer batteries or similar memory members or combinations thereof, the data (ie the digitized and compressed images) in this memory being able to be read by a suitable known reader connected to a video monitor, such as a television set (neither being shown) ; and an interface circuit block 55 to which the display 21, the microspeaker 22, a collision sensor 58 (such as a known inertia switch, a usual electronic mechanical shock sensing circuit or equivalent mechanical and/or electronic means), and the pushbuttons 23 and 24 are connected, said interface 55 being arranged for connection to members external to the device D, for example the memorized data reading member, via a connection member 56 (coinciding with the said member 26). Specifically, one or more sensors (visual, acoustic, inertial etc.) can be connected to the member 56 in order to feed the device D with information relative to the operation and/or activation of vehicle members (such as brakes, direction indicators, steering member etc.), to enable the device to make a circular recording or a recording subsequent to the accident of the "internal state" of the vehicle. The purpose of this is to improve the characterisation of the causes of the accident.

The collision sensor 58 can be an analog sensor (not of on-off type) of a type able to evaluate any vehicle deceleration and on the basis of this to decide whether a collision has occurred (sudden instantaneous deceleration) -v not (slow deceleration). As stated, the functions of this se: .;<,r can also be computed by

the unit 50 , which by evaluating in real time the images obtained by the telecamera recognizes whether a collision has occurred or not . fΦ

The interface-and the members (21, 22, 23, 24, 56, 58) connected to it define a part of the circuit 3 (known for simplicity as the user circuit) indicated in the figures under examination by 57. The part 57 also comprises a signal receiver 90 (of known type) able to receive the signal generated by the remote control 27.

A clock generator 59 is also"-- connected to the bus 51 to provide timing for the unit 50. This generator also enables the data relative to the images obtained by the telecamera 4 to be allotted a date and time; in other words the generator 59 acts as a clock- calendar and is provided with its own buffer battery. It enables the date on which the images were obtained to be exactly defined together with their exact succession in time, this being very important in defining the accident causes and responsibilities.

The circuit 3 is also connected to a usual converter member (not shown) for converting the voltage and amperage of the vehicle battery 32 to the values required for correct operation of the components of said circuit. This converter also enables the power supply to the circuit 3 to be stabilized.

The unit 50 is for example a microprocessor circuit cooperating with the data compression member 53 (as in Figure 6). Alternatively this unit can itself perform the data compression function (Figure 7) or cooperate with a known direct access memory member 60 as in Figure 8.

The method of the invention will now be described in relation to the use of the aforedescribed circuit 3.

It should be noted that the device D is able to record optically and dynamically, in digital form in real time, the environment surrounding the vehicle (or its interior) on which it is mounted

while the vehicle is moving or, if required, while it is at rest. The method of recording is circular, ie new recordings replace older recordings after a time interval which is preset but can be changed at will by the device manufacturer or by the user. The recordings remain in other respects unaltered for very long time periods, according to the type of memory used (54 or 60) or a combination thereof, and in any event sufficient to enable them to be transferred onto other memory supports external to the device, for example to enable the memorized images to be viewed. In addition, in the case of vehicle collision, image recording ceases after a predetermined time 'period, however the data remain in the memory 54 (until zeroed by the pushbutton 23 unless an accident has occurred, in which case this pushbutton is deactivated, or otherwise zeroed by an analogous pushbutton of the remote control 27) to enable the data to be viewed so as- ^' to determine the accident causes and responsibility.

The recording can however be halted manually by the pushbutton 24.

To describe the method of the invention reference will again be made to Figures 9 and 1S. It will be assumed that the contactors 30 and 41 have been closed (by the key 28 or remote control 27) to hence power the device D. This corresponds to the block or stage 61 of Figure 10.

The unit 50 of the circuit 3 then executes in known manner (block 62) a self-diagnosis of the functionality of its components and of those connected to it. If there is a malfunction or error condition, the light-emitting display 21 and audio display (loudspeaker) 22 are activated. This is indicated in block 63 of Figure 10 ^' . Said activation lasts for a predetermined time (set by the unit 50), after which the operation of the device D automatically cuts out.

If there is no error condition, the unit 50 activates the telecamera 4 together with each component of the circuit 3 (block 64) to hence start to acquire images from said telecamera (or

microtelecamera) (block 65). The unit then compresses the digital (or digitized) data or images (block 6θ_) by feeding them to the compression member 53 or directly executing the compression by its own command algorithms (Figure 7).

After the images have been compressed, the data relative to each compressed frame are fed to the memory member (or memory) 54 (block 67). This memory memorizes in FIFO manner (block 68) by constantly positioning the new compressed images at the head of the preceding until the memory is saturated. ^' When this occurs the oldest images are removed c make space for the most recent.

The unit 50 then checks whether a collision has occurred (block 69) by "interrogating" the shock sensor. If the response is negative, the unit checks whether there has been a normal recording stop command (by pressing the pushbutton 24, block 70, in which case it halts the recording) or whether a data zeroing command for the memory 54 has been fed (by pressing the pushbutton 23, block 71, in which case it resets the memory, block 72). If there has been no zeroing request, or following such a request if there has been one, the procedure recommences with block 65. It should be noted that if a stop request has been made by generating the stop command, the procedure followed by the unit 50 halts, because of lack of the principal power supply, after a predetermined number of seconds defined by the time characteristic of the relay 35.

If however ^" a collision has occurred, this is indicated by a halt- memorization signal generated by the collision sensor 58 and is detected in the block 69. In this case the unit 50 sets its own internal timer (block 75), not shown, which halts the operation of the circuit 3 for a time at least equal to the characteristic time of the relay 35 (so that ^" of the vehicle engine stops, the procedure followed by the unit 50 is not blocked by the key 29 being positioned in position S). It then checks whether the time defined by its own timer has lapsed (block 76). If this time has not yet lapsed the unit 50 executes operations analogous to those

described with reference to blocks 65, 66, 67 and 68 (indicated by 77, 78, 79 and 80) and returns to check whether the time set by the timer has expired. If it has (ie if the predetermined time period during which, after collision, the images obtained by the telecamera 4 are recorded has expired), the procedure ceases.

The box casing 1 can now be removed from the vehicle and the contents of the memory 54 read (or copied onto another optical or magnetic support) by connecting a suitable known reader to the member 56 connected to the serial port 55 of the circuit 3.

From this reading it is hence possible to determine the causes of and responsibility for the accident in which the vehicle on which the device D has been mounted is involved.

Summarizing, the present invention provides a device for recording the stages immediately prior to and following an accident involving a vehicle, and has the following characteristics:

1) circularity of digital recording on a memory member, ie the retaining of memorized information until the next recording;

2) real-time compression of digital or digitized images obtained by the telecamera in order to extend to a maximum the memorizable recording period;

3) correlation between detection of the collision and stoppage after a predetermined recording period.

A preferred embodiment of the invention has been described. Other embodiments are however possible in the light of the aforegoing description (such as one using electrical or electronic components, with or without the use of a microprocessor, for handling and memorizing the images obtained by the optical sensing member or telecamera 4); such further embodiments are to be therefore considered as falling within the scope of the present document.